1. Field of the Invention
This invention is generally related to bow string releases and is specifically directed to a release having over and under jaws and an axial adjustment mechanism.
2. Discussion of the Prior Art
Various forms of mechanical archery bow string releases have become increasingly popular in recent years because they provide uniform control of a bow string and an increase in accuracy by effecting a consistent, controlled release of an arrow. Such releases are typically used to maintain the bow string in a cocked position in which the bow string is flexed against the tension of a bow for propelling an arrow supported on the bow string. When a drawn arrow is released from a release mechanism, the release is usually relatively rapid and at a point approximately in line with the centerline of the bow so that the bow string delivers most of its thrust directly along the major axis of the arrow. When tabs or fingers are used to release a bow string, the bow string tends to roll off the fingers or tab and be deflected sideways during release such that the bow string follows a serpentine path, failing to maximize energy delivery directly along the major axis of the arrow.
An arrow itself is generally comprised of a shaft with a point mounted on one end and a nock mounted on the opposite end. A standard arrow nock has a bow string receiving groove or notch defined by spaced apart legs extending from a base. The notched nock is configured to receive a bow string and insure stability of the arrow during cocking and release of the bow string. When an arrow is loaded on a bow in this manner, the legs of the arrow nock extend beyond the bow string toward the archer such that an arrow can pivot from side to side about the bow string. When loaded, the nock of an arrow is preferably seated at or near the mid-point of the bow string to insure that the flight of the arrow is as true as possible.
Most bow string releases employ a trigger mechanism to activate the bow string retaining and release mechanism. Typically, the release mechanism engages a bow string at a single point, utilizing either pivotable jaws or a pin and flexible eyed loop as the sear means for retaining the bow string. Some releases attach directly to the corresponding bow string and other releases cooperate with bow string mounted anchors or arrow nock holders having portions adapted to be engaged by the releases. In any event, the releases attach at or near the mid-point of the bow string, adjacent the arrow nock, to enhance thrust of the arrow. One drawback to these prior art devices is that such release mechanisms are not generally coaxially aligned with the arrow shaft. Rather, the release engages the bow string at a single point just above or below the arrow, set off from the axis of the arrow. In such cases, the bow string at its point of contact with the arrow nock is angled relative to the arrow nock rather than being flush against the base of the arrow nock. This alignment can effect the arrow's flight path, causing the arrow to wander during flight. For example, a release mechanism engaging a bow string just above an arrow is likely to cause the flight path of an arrow to angle downward, while a release mechanism engaging a bow string just below an arrow is likely to cause the flight path of an arrow to angle upward.
One solution to permit coaxial alignment of a release mechanism with an arrow is to provide structures or "receivers" that attach to bow strings to support an arrow nock and provide a point of attachment for a release mechanism. For example, U.S. Pat. No. 5,537,986 teaches a device comprised of an open-mouthed, U-shaped member that generally attaches to a bow string at substantially the mid-point of the bow string. The ends of the U-shaped member attach just above and just below the arrow nock with the bowl portion extending behind the bow string such that the apex of the bowl is along the axis of a seated arrow. The release mechanism attaches to the backwardly extending bowl of the U-shaped member. This type of receiver permits a release mechanism to engage the bow string in substantially coaxial alignment with an arrow and allows the nock of a drawn arrow to seat flush against the bow string as the string is drawn and released. In other words, the portion of the arrow string against which the nock seats is maintained substantially perpendicular to the axis of the arrow rather than skewed relative to the arrow's axis.
A release mechanism that attaches directly to a bow string and permits coaxial alignment of an arrow and the release is taught in U.S. Pat. No. 5,020,508 issued to Greene. In Greene, the release is provided with two pivotable jaw heads, wherein each jaw head is U-shaped to provided upper and lower bow string engagement structures. Each U-shaped jaw is pivotally mounted on a base to move into and out of engagement with the other U-shaped jaw. Specifically, upper and lower bow string members mate with their respective counterparts to secure the bow string at two spaced apart points on opposite sides of a seated arrow nock. The jaws are disposed to simultaneously move laterally toward or away from one another as they pivot about their respective pivot pins under actuation by a trigger mechanism. One drawback to such a device is that the pivotal nature of both jaws increases the complexity of the device and renders it more susceptible to failure than less complex devices employing fewer moving parts. This is especially undesirable under typical conditions in which such bow string devices are used, where the environment may include rain, snow, water, mud or other debris that could hinder operation of moving parts. In addition, typically, the more moving parts, the greater the relative cost of the device.
In many cases, bow string releases such as those described above are secured to an archer's wrist, permitting the release to be held in a ready position while freeing the fingers of the hand for other tasks. Also, by attaching the release to an archer's wrist, the amount of strain on the hand is greatly decreased when high draw weight bows are utilized, which is typical in archery hunting and archery tournaments. Many various wrist straps and harnesses are available for bow string releases, such as for example, the widely accepted V-type wrist strap. Commonly, the release is pivotally attached, via an elongated, cylindrical shaft, to an enlarged palm area or base which forms part of the strap.
One drawback to such wrist mounted straps is that the devices are not disposed to accommodate hands of varying sizes, such that the trigger may not be properly positioned to comfortably manipulate the trigger mechanism. One solution to such a drawback is proposed in U.S. Pat. No. 5,596,977 issued to Scott. The Scott patent teaches a bow string release device in which an adjustment mechanism is provided to alter the length between the wrist strap base and the release mechanism. Specifically, Scott teaches an inner shaft that slides inside an axial bore of an outer shaft. The inner shaft is attached to a wrist strap and the outer shaft is attached to a release mechanism. The outer shaft is provided with a number of transverse radial holes spaced apart along its length and the inner shaft is provided with at least one transverse hole for radial alignment with one of the holes of the outer shaft. The inner shaft is secured within the outer shaft by a bolt that extends radially through the aligned holes of the inner and outer shafts. The position of the inner shaft relative to the outer shaft, and hence the overall distance of the release mechanism from the wrist strap, can be altered by sliding the inner shaft within the outer shaft until the inner shaft hole is radially aligned with a different hole of the outer shaft.
A drawback to the adjustment mechanism of the Scott patent is found in the functional range permitted by the device. Specifically, the adjustment lengths of the Scott patent is confined to the spacing of the apertures along the outer shaft of the device. The device will only properly fit an archer's hand if the archer's hand size correlates to one of the spaced apart radial holes. Another drawback to the Scott patent is that the pin or bolt used to secure the inner and outer shafts together is a separate element that must be manipulated. As a separate element, the piece may be lost or dropped, rendering the release mechanism virtually unusable. Furthermore, as described above, the environments in which a bow string release device are typically may further frustrate use of a pin/adjustment hole configuration of the Scott patents, rendering the adjustment mechanism difficult to manipulate. For example, a gloved archer may have difficulty manipulating the small pin of the Scott patent, or debris may clog the axial holes used to lock the adjustment mechanism. Furthermore, proper axial alignment of the outer and inner shafts to permit a bolt to be inserted therein may be difficult to achieve, especially in a harsh environment or low light conditions.